*

Giant Crab occurs from WA to TAS with weakly connected stocks throughout this range. The stock associated with each cluster of fishing is assessed here. The Western Australian and South Australian stocks are sustainble. The stock West of Bass Strait is recovering. The stock East of Tasmania is undefined due to limited fishing and data.

Giant Crab is continuously distributed across its range from Western Australia to East of Tasmania. Movement of giant crab post-settlement is limited. Planktonic larval duration is around 50 days, with larval release occurring along the edge of the continental shelf. The shelf is a high current area, facilitating dispersal, and oceanographic modelling has indicated that Giant Crab dispersal occurs over reasonably large spatial scales [Gardner 1998; Gardner and Quintana 1998; Williams et. al. 2009]. However, given the large spatial scale of the distribution and features that disrupt dispersal (such as the Bass Strait) the species is likely to consist of a series of local populations with moderate connectivity within the meta population. An FRDC project is currently underway which will provide further clarification on stock structure for future assessments (FRDC Project 2021-025 Resolving the biological stock structure of Southern Ocean crab fisheries).

Fishing occurs in four spatial clusters which are sufficiently separated that each cluster is likely to be fishing a local stock that has a low level of connectivity with the other stocks. The stock "West of Bass Strait" is fished by both Victoria and Tasmania. This stock previously had differing assessments for the two jurisdictions which resulted in an assessment on a jurisdictional basis. However, these differences have now been resolved. Consequently, assessment of stock status is presented here at the biological-stock level—Eastern Tasmania, South Australia, West of Bass Strait, and Western Australia.

Western Australia

Historically, limited data were available for Giant Crab targeted fishing in Western Australia, with catches being generally either a by-product of Southern Rock Lobster fishing, or part of a combined catch of other deep-sea crabs. Recently, logbook data for target Giant Crab catches have become available. Catches of Giant Crabs in Western Australia fluctuated, increasing from 4.8 t in 2009–10 to 14.6 t 2012–13, before generally remaining around 10 t from the 2014–15 to 2019–20 seasons. In the 2021–22 fishing season, the South Coast Crustacean Managed Fishery, which lands most Giant Crab in Western Australia, was transitioned to individual transferrable quotas. The total allowable catch across the four fishing zones for Giant Crab has initially been set conservatively at 6.4 t. Current landings are taken across a wide geographic range when compared to other jurisdictions, and there are large portions of the stock in Western Australia (particularly east of longitude 125°E) that are not being exploited. The above evidence indicates that the biomass of this stock is unlikely to be depleted, that locally sourced recruitment is unlikely to be impaired, and that the current level of fishing pressure is unlikely to cause the stock to become recruitment impaired.

On the basis of the evidence presented above, Giant Crab in Western Australia is classified as a sustainable stock.

Giant Crab biology [Gardner 1998; McGarvey et. al. 1999; Williams et. al. 2009,]

Distribution of reported commercial catch of Giant Crab

South Australian data are from quota holders in the 2016–17 fishing season (October 2016–May 2017), Victorian data are for the 2021–22 fishing season (November 2021–September 2022), Tasmanian data are for the 2022-23 fishing season (March 2022 – February 2023) and South Coast Crustacean Managed Fishery (Western Australia) data are for the 2019–20 financial year. 

Victoria – Indigenous (Management Methods). A person who identifies as Aboriginal or Torres Strait Islander is exempt from the need to obtain a Victorian recreational fishing licence, provided they comply with all other rules that apply to recreational fishers, including rules on equipment, catch limits, size limits and restricted areas. Traditional (non-commercial) fishing activities that are carried out by members of a traditional owner group entity under an agreement pursuant to Victoria’s Traditional Owner Settlement Act 2010 are also exempt from the need to hold a recreational fishing licence, subject to any conditions outlined in the agreement. Native title holders are also exempt from the need to obtain a recreational fishinglicence under the provisions of the Commonwealth’s Native Title Act 1993.

Commercial catch of Giant Crab - note confidential catch not shown

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